Audiphone-transmitter.



Patented May 14, 1912.

C. E. WILLIAMS.v

AUDIPHONE TRANSMITTER.

APPLIGATION FILED 11mm. 1911.

CHARLES E. WILLIAMS, OF CHICAGO, ILLINOIS.

AUDIPHONE-TRANSMITTER.

i Specification of Letters Patent.

-Appucation' aiefl January 14, 1911.

YPatented Mav 14, 1912.

Serial No. 602,598.

To all who/m. t may concern Be it known that I, CHARLES E. Vnf Lnnrs, a citizen of the United States, residing at the city'of Chicago, in the county of Cook and State ot' Illinois, .have invented a new and useful Improvement in Audiphone-'lransmitters, of which the following is a specification. f

My invent-ion relates to audiphone transmitters by which external sounds are changed to electric impulses to be thus transmitted to a receiver by which they are reproduced in audible form. As such instruments are usually carried by the person and concealed in the clot-hing of the user,sounds reach them in mutlled condition, and it is necessary that such sounds be presented to the currentcontrolling devices with the greatest possible amplitude.

lt is the object of' my invention to aid in such presentation, and, by applying the Aprinciples thereof, to the transmitters now inv use l am able to transmit sounds therefrom with added fullness and resonance and greatly reduce the effect ot extraneous sounds. v In illustrating the principles of my invention, for convenience I will show it in substance as applied to a transmitter invented by me and which t'orms the subject matter of U. S. Patent No. 911,101, and dated February 2, 1909, but it is to be understood that this invention is not merely an improvement on the device, but that it is equally applicable to other transmitters.

ln the drawings-Figure 1 shows a side elevation of an audiphone transmitter with my improvement applied thereto; Fig. 2 is a front elevation thereof; Fig. 3 is a central vertical section. "n

Further describing my invention with reference to the drawings, in which like characters of reference denote like`- parts throughout: 1 represents a metallic 'trame work or supporting piece, havin f a depressed portion 9. which forms an ectrode chamber 2. The carbon electrode 3 is seated therein, and may be secured thereto by the attachingr screw and nut 4, which has the usual insulation 4. 5 represents a depression or opening in the said electrode filled with small carbon particles or balls which are adapted to contact with the diaphragm 6 in the rear of the instrument and of said electrode chamber'. The s aid d laphragm is held in place by a locking ring At the rear of the instrumentis a cover or i protector within which the diaphragm 6 vibrates. It is secured in place so that the edges thereof rest. upon the frame ortion 1, by means of a bridge 10. Openings 11 through the frame 1 and the annular member 9 permit free ingress and egress of air into the chamber 12 thus formed, and through such openings the sound waves are permitted to pass.

At the front ot the instrumentis acover or resonator 13 secured in place concentrically with the revcrberatory chamber 9, and forming a second annular reverberatory chamber 13 outside of the first. The edges of said reso nator are extended substantially to the peripheral edges of the instrument and beyond the openings 11 which communicate with the rear chamber. Such extension is adapted to receive the vibrations of air set up in the rear chamber and to protect the said openings 11 against the ingress of external sounds when they first come in contact with the instrument. The addition of this resonator, whereby is formed an additional reverberatory chamber of annular form between it and the first reverberatory chamber, is found to add greatly to the sensitiveness of the instrument. It increases and amplifies the volume of sound which is produced whereby correspondingly eifective electrical impulses are set up for transmission to the receiver. And, to a great extent, the production of extraneous sound, or its ct't'ect of interfering with the clear transmis-l sion of normal sounds is prevented.

I claim: i

1. In an audiphone transmitter provided with apparatus for electrically transmitting sound waves, a closed reverberatory chamber on one side of said apparatus, and an externally opening reverberatory chamber on, the other side of said apparatus; the combination therewith of a resonator having an open side and secured in o erative relation to said externally opening chamber, substantially as described.

Q. 'lhe combination in an -audiphone transmitter of apparatus for electrlcally leo transmitting sound Waves, and provided With a. diaphragm, a closed reverberatory chamber in frontl of said diaphragm, a reverberatory chamber in the rear of said dia phragm and provided with peripheralv openings; and a resonator having an open side placed in front of and external to the closed reverberatorychamber and having the peripheral edges thereof adapted to cover and be spaced from the openings inthe said rear reverberatory chamber. 3. In an-audiphone transnntter, the comv I bination of a closed electrode chamber having a resilient Wall, a reverberatory chamber having peripheral openings, a vibratoryL f diaphragm between said chambers, and a resonating chamber concentric With the re- 4 my hand, this 7th day of lJanuary ing a diaphragm, caps covering the electrodes, and a cap mounted upon and being of greater diameter than one of the first,

named caps and having its outer edge free. In Witness Whereof,'1 have hereun) scte 1911, in the presence of two subscribing Witnesses.

CHARLES E. VVILLIABIS. Witnesses C. K. CHAMBERLAIN, A. S. PHILLIPS. 

